At one point Dr. Martin thought he had identified the hematopoietic tissue in the Sicyonia ingentis shrimp. However, further work suggested that these particular organs were more likely involved in the clearance of foreign materials from the body. Further work has identified another thin, indistinct film between the foregut and the exoskeleton which may be the true hematopoietic tissue. My project will involve verifying that this film is indeed the hematopoietic tissue. I will inject the shrimp with bacteria, substantially decreasing their total red blood cell count, and then look at the identified tissue and check for a significant increase in the mitotic index. This will help confirm whether this film is actually the hematopoietic tissue.